So-called keyless start and entry systems for motor vehicles are known per se. In such systems, a user only needs to carry a key that comprises a transmitting and receiving unit in order to gain access to his vehicle and can then usually start the motor of the vehicle by actuating a start/stop button. The motor vehicle in such cases therefore does not have to be actively unlocked and it is not necessary to insert and turn a key in an ignition lock of the motor vehicle. Furthermore, start and entry systems for motor vehicles are known, in which a motor vehicle can be unlocked, locked and started by means of a Smartphone, in particular via near-field communication between Smartphone and motor vehicle.
DE 10 2014 107 186 A1 discloses a modular unit having an interface for a communication device which can be a Smartphone, for example. The modular unit is suitable for receiving signals of a communication module on the vehicle side via a wireless connection and to make the signals available to the communication terminal.
DE 10 2014 112 849 A1 discloses a method for remote control of at least a first function of a security device of a vehicle. For the remote control of this at least one function, a remote control device, for example, in the form of a Smartphone, is proposed. Without active operation of the remote control device, it is possible to unlock the vehicle, for example, just by touching an exterior handle of a door.
In addition, as long as the remote control device is in the vehicle interior, it is also possible to start the vehicle via a start-stop button in the vehicle interior, without having to insert a vehicle key into an ignition lock.
In addition, DE 10 2014 101 086 A1 discloses a mobile communication device in the form of a Smartphone, by means of which a motor vehicle can be unlocked, locked, and keylessly started via a near-field communication.
In particular, when a motor vehicle can be unlocked, locked and started via an NFC-capable, that is to say near-field communication-capable, communication device, for example, in the form of a Smartphone, as well as by means of a vehicle key comprising a transmitting and receiving unit, undesired side effects can sometimes occur. For example, functional limitations or unauthorized ads in a display device of the motor vehicle, such as, for example, an instrument cluster, for example, could arise. In addition, disadvantages can also result in terms of energy consumption when the two systems, that is to say the systems for near-field communication and for communication with the transmitting and receiving unit of the vehicle key, are continuously active.